How real are Asian dating sites

Which dating sites in Asia are fake?

I met a man four months ago. He is very charming and funny.

He had shown interest in me from the start. At first I noticed that he often teased another woman he had known a little longer than me, but I thought it was just his way. We gradually got to know each other very well and spend a lot of time together. I am looking for his company and he is looking for mine.

But then I got a conversation from the two of them (him and the woman he had known a little longer) and he really snuck into her and flirted with her. I ignored it for the first time, but since then I've regularly noticed him beaming at her or complimenting her. On her birthday, he wanted a hug from her almost every half hour. He pulled the same off on my birthday too.

He also looks at other women when we talk to each other and recently he said that he is really looking forward to moving, then he sees a certain person more often. I asked who and he said that the woman lives nearby.

He flirts with other women in front of me (not only with her) and he always makes strange hints about other women when I sit or stand next to him.

Isn't it usually the case that when a man gets to know each other seriously, he doesn't flirt with other women and make silly innuendos?

I know that he is 100% interested in me and we have also met privately, but I get more and more the feeling that I am just one of many and that he behaves the same way with other women as he does with me.

Could it be that I'm just one of many? And why does that make me jealous?